As part of the new agreement, FUN88 - which has been a familiar sight on first team kit since summer 2017 - will continue to feature on the front of players' shirts and training wear.
Established in Asia in 2008, FUN88 has a significant online following around the world and offers sports betting, live casinos, slots and keno games in multiple languages.
The brand has also developed a popular presence on social media with Newcastle United fans, with thousands of Magpies supporters interacting with its accounts and many benefitting from its competitions and ticket and shirt giveaways over the last three years.
"BUILDING ON THE SUCCESS OF OUR PARTNERSHIP TO DATE, WE LOOK FORWARD TO THIS NEXT PHASE AND WORKING TOGETHER TO ENGAGE FANS AND GROW OUR COLLECTIVE REACH AROUND THE GLOBE."LEE CHARNLEY, MANAGING DIRECTOR
Lee Charnley, Newcastle United's managing director, said: "We are delighted FUN88 has renewed its relationship with Newcastle United and committed its support to the club over a number of years to come.
"Building on the success of our partnership to date, we look forward to this next phase and working together to engage fans and grow our collective reach around the globe."
A FUN88 spokesperson said: "FUN88 is delighted to continue its association with Newcastle United Football Club.
"Together with the club, we live the dream of expanding our fan base across all continents, especially in Asia.
"FUN88 is optimistic that this partnership will assist us in becoming the leading gaming and entertainment platform in countries across the world."